A wine fault or defect is an unpleasant characteristic of a wine often resulting from poor winemaking practices or storage conditions, and leading to wine spoilage. Many of the compounds that cause wine faults are already naturally present in wine but at insufficient concentrations to adversely affect it. In. fact, depending on perception, these concentrations may impart positive characters to the wine. However when the concentration of these compounds greatly exceeds the sensory threshold, they replace or obscure the flavors and aromas that the wine should be expressing. Ultimately the quality of the wine is reduced, making it less appealing and sometimes undrinkable.
The oxidation of wine is perhaps the most common of wine faults, as the presence of oxygen and a catalyst are the only requirements for the process to occur. It is also known as maderized wine, from Madeira wine, which is intentionally oxidized. Oxidation can occur throughout the winemaking process, but more typically occurs after the wine has been opened and a portion remains in the bottle.
A variety of mechanisms and devices have been developed in the past in order to overcome or at least ameliorate oxidation of wine in a partially opened wine bottle. These include closures which allow the venting of gases from an open bottle which has been resealed, the application of a vacuum technology to partially withdraw any gases from an upper portion of the bottle.
Whilst all of these methods or devices have varied success, there remains the problem of minimising oxidation in previously opened partially consumed bottled wine.
Further, other beverages may also suffer from a loss of quality due to oxidation.
It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.